1. INSECT PESTS OF CRUCIFER
R. Regmi
Assistant professor
Department of entomology
2. INSECT PESTS OF CRUCIFER
• Cabbage, cauliflower, broccoli, radish, mustard
etc are major crucifer crops.
• Many insect pests infect the crucifer crops
reducing the productivity and quality of
product.
9. Cabbage butterfly, Pieris
brassicae (Lepidoptera:
Pieridae)
• It is serious pest of cabbage, cauliflower, knol khol & also attack turnip,
radish, sarsoo, mustard and other cruciferous crops.
• Damage is caused by caterpillars only, when full grown measure 40-50
mm in length.
• The young larvae are pale yellow and become greenish yellow later on.
The head is black and the dorsum is marked with black spots. The
body is decorated with short hairs.
• The butterflies are pale white and have a smoky shade on the dorsal
side of the body.
• The wings are pale white, with a black patch on the apical angle of each
forewing and black spot on the costal margin of each hind wing.
• The females measure 6.5 cm across the spread wings and have two
conspicuous black circular dots on the dorsal side of each forewing.
• Males are smaller than the females and have two black spots on the
underside of each forewing.
10.
11. Life cycle:
• This pest appears on cruciferous vegetables at the beginning of October
and remains active up to the end of April.
• From May to September, the pest is not found in the plain but breeding
takes place in the mountains.
• The butterfly very active in the field and lay, on an average, 164 yellowish
conical eggs in clusters of 50-90 on the upper or lower sides of the
leaves.
• The eggs hatch in 11-17 days in November- February & 3-7 days in March
– May.
• The caterpillars feed gregariously during the early instars & disperse as
they approach maturity.
• They pass through five stages & are full fed in 15-22 days during March –
April and 30-40 days during November –February.
• Pupation generally takes place in cocoon hanging in wall, branches and
other plant parts.
• The pupal stage lasts 7.7- 14.4 days in March – April and 20-28 days in
November –February.
• The butterflies live for 2.5 -12.5 days.
12.
13. Damage:
• The caterpillar alone cause damage.
• The first instars caterpillar just scrap the leaf
surface
• Whereas the subsequent instars eat up leaves
form the margin inwards, leaving intact the
main veins.
• Often entire plants are eaten.
14. Management:
• Hand picking and mechanical destruction of caterpillar
during early stage of attack can reduce infestation.
• Conservation of natural enemies like Assasian bugs,
paper wasps etc.
• Release of Trichogramma, Apanteles glomeratus etc.
• Spray commercial formulation of Bacillus thuringiensis
@1-2 g/liter of water
• Spray 1 liter of malathion 50EC in 250 liters of water
per ha & Repeat spraying at 10- day interval if
necessary.
15. Diamond Back Moth, Plutella xylostella
(Lepidoptera: Plutellidae)
• Serious pest of cauliflower & cabbage, but also
feeds on many other cruciferous crops,
solanaceous and liliaceous crops.
• Damage is caused by the caterpillars
• Earlier stages feed in mines on the lower side of
cabbage leaves.
• When full grown, the larvae measure about 8-12
mm in length and are pale yellowish green with
fine black hair scattered all over the body.
• The moth measure about 8-12 mm in length and
are brown or grey with conspicuous white spots
on the forewings, which appears like diamond
patterns when the wings lie flat over the body.
16.
17. Life cycle:
• This insect is active throughout the year.
• Yellowish eggs of pin-heads size are laid singly or in batches of 2-
40 on the underside of leaves.
• A female may lay 18-356 eggs on her life time.
• The eggs hatch in 2.5-9 days .
• The newly hatched caterpillar bore into the tissue from the
underside of leaves and feed in these tunnels.
• At first, their presence is detected by only from the blackish excreta
that appear at the mouth of each tunnel, but in second instar, the
mines become more prominent.
• In the third instar, the caterpillar usually feed outside the tunnels.
• The larvae of the fourth instar feed from the undersides of leaves,
leaving intact a parchment like transparent cuticular laryer on the
dorsal surface.
18. Continue life cycle
• The larvae are very sensitive to touch, wind or other
physical disturbances and readily feign death.
• They become fully grown in 16.6-8.6 days
• Before pupating, the larva constructs a barrel shaped silken
cocoon, which is open at both ends and is attached to the
leaf surface.
• The pupal stage lasts 4-5 days at 17-25 ºC
• The moths may live for as long as 20 days.
• The life cycle is completed in 15-18 days during September-
October and there are several generation in a year.
19. Damage:
• Caterpillar damages the leaves of cauliflower,
cabbage and rape-seed particularly in the heart
of the first two.
• Central leaves of cabbage or cauliflower may
riddled and the vegetables rendered unfit for
human consumption.
• The pest is serious when it appears on the early
crop in August-September.
•
20. Management:
• Remove and destroy all the remnants, stubble, debris etc
after the harvest of the crop and plough the fields
• Tomato intercropped with cabbage inhibit or reduces egg
laying by diamond back moth
• Mustard can be used as trap crops. Two rows of mustard for
every 25 rows of cabbage.
• Release larval parsitiod, Cotesia plutellae @200 pupae per
ropani
• Spray commercial formulation of Bacillus thuringiensis @1-
2 g/liter of water
• Spray 0.05% solution of malathion 50%EC to manage
21. Cabbage flea beetle, Phyllotreta cruciferae
(Coleoptera; Chyrosmelidae)
• The flea beetles attack almost all the cruciferous plants.
• The common fields crops like mustard, Broad leaf mustard, radish, turnip,
cabbage, cauliflower and Knol-khol and some winter flowering plants
namely dahlia, sweet pea, antirrhinum etc.
• The dorsum of the adult beetle P. cruciferae is metallic blue in color with
greenish hue.
• The body is elongated narrow in front but broad distally.
• The beetle is round at the anal end.
• The head is finely punctate and the antennae extend beyond the middle of
elytra.
• The female beetle measures 2.0 mm in length while the male beetle
measures 1.8 mm.
• The larva is dirty white in colour with pale white head measures about 5
mm in length.
23. Life cycle:
• This pest is active throughout the year except during the winter months,
when it hibernates in the soil or among plant debris.
• The over wintered adult beetles emerge in the last weeks of February or
in the beginning of March & settle on the growing cruciferous plants.
• The female beetle laid 50-80 creamy white eggs singly in the soil around
the host plants, during the oviposition period of 25-30 days.
• The incubation period ranges between 5-10 days.
• The larva is very active and feeds on the tender roots of the host plant,
which moult thrice during a total larval period of 9-15 days.
• The larva before entering into the prepupal stage wriggles out of the
mined roots & prepares an earthen cell, 0.5 mm long, in the vicinity of the
infested plants where it pupate.
• The pre pupal period is 2-4 days and the pupal stage lasts 8-14 days.
• There are 7-8 generation of this pest in a year.
24. Damage:
• The adult mostly feed on the leaves by making
in-numerable round holes in the host plants.
• The stem, the flower & even pods may also be
attacked.
• The old eaten away leaves dry up, while the
young leaves are rendered unfit for
consumption.
• A special kind of decaying odour is emitted by
the cabbage plants attacked by this pest.
25. Management:
• Field sanitation, Deep ploughing and removal
of alternate hosts.
• Lacewing larvae and Big eyed bug are
predator for management of flea beetle.
• Use of chemical pesticides like Malathion or
cypermetrin @2-3 ml/lit of water.
26. Mustard Sawfly, Athalia lugens
(Hymenoptera: Tenthredinidae)
• The mustard sawfly is widely distributed in Indian
subcontinent.
• It feeds on mustard, rapeseed, cabbage, cauliflower, Knol
khol, turnip, radish etc.
• Damage is done by the larva, which are dark in color and
have 8 pairs of prolegs.
• There are five black stripes on the back and the body has
wrinkled appearance.
• A full grown larva measures 16-18 mm in length.
• The adult are small orange yellow insect with black
marking on the body & have smoky wings with black veins.
28. Life Cycle:
• The mustard sawfly breeds from October to March and the larvae
rest in their pupal cocoons in the ground during summer.
• The adult emerge from these cocoons early in October.
• Adult live for 2-8 days and lay 30-35 eggs singly, in slits made with
saw like ovipositors along the underside of the leaf margins.
• The egg hatch in 4-8 days and the larvae feed exposed in groups of
3-6 on the leaves during morning and evening.
• They remain hidden during the day time and, when disturbed, fall
to the ground and feign death.
• They pass through seven stages and are full grown in 16-35 days.
• The full fed larvae descend the plant and enter the soil to a depth
of 25-30 mm.
• There, they pupate in water proof oval cocoon made of silk and
emerge from them as adults in 11-31 days.
• Thus, the life cycle is completed in 31-34days and pest completes 2-
3 generation from October to March
29. Damage:
• The grubs alone are destructive.
• They bite hole into leaves preferring the young
growth & skeletonize the leaves completely.
• Sometime, even the epidermis of the shoot is
eaten up.
• The older plants, when attacked, do not bear
seed.
30. Management:
• Applying irrigation in seedling stage
• Collection and destruction of larva at evening and
morning.
• Field sanitation, deep polughing
• Perilissus cingulator Morely, parsitiod of grub and
bacteria Serratia marcescens Bizio infect the larvae of
sawfly.
• Use of bio pesticide like margosom, Annosom show
significant effect on management of this pest.
• Spray one liter of malathion 50 EC per ha in 150-200
liters of water.
31. Mustard Aphid, Lipaphis erysimi
(Homoptera: Aphididae)
• The mustard aphid is a serious pest of cruciferous
crops mustard, sarson, cabbage, cauliflower,
Knol-khol etc.
• The damage is caused by both nymphs and
adults, which are pale greenish insects.
• They are seen feeding in large number, often
covering the entire surface of flower buds,
shoots, pods etc.
32. Life cycle:
• This insect is most abundant form December to march when
it infests various cruciferous oilseeds and vegetables.
• During summer, it is migrate to hills and there is some
evidence that aphids also survive on abandoned stray plants
of cabbage and on cruciferous weeds in the plains.
• The pest breeds parthenogenetically and the females give
birth to 26- 133 nymphs.
• They grow very fast and are full fed in 7-10 days.
• About 45 generation are completed in a year.
• Cloudy and cold weather (20°C or below) is very favorable
for the multiplication of this pest.
• The winged forms are produced in autumn and spring, and
they spread from field to field and from locality to locality.
33. Cabbage Aphid, Brevicoryne brassicae
(Homoptera: Aphididae)
• Cabbage aphid are 1.6- 2.8 mm in body length.
• They have short siphunculi and triangular cauda,
their body is covered with grayish- white mealy
wax, which is also secreted to the surface of
plant & extends throughout the colony.
• They are commonly occurs in dense colonies,
often covered with wax droplets.
• It is serious pest of cauliflower, cabbage,
brocauli, radish, mustard etc.
34.
35. Damage:
• Both Nymph and adults suck cell sap from
leaves, stem, inflorescence, or the developing
pods.
• Due to the very high population of the pest
the vitality of plants is greatly reduced.
• The leaves acquire a curly appearance, the
flower fail to form pods and the developing
pods do not produce healthy seeds.
• The yield of an infested crop is greatly
reduced.
36. Management:
• Early sowing the crop, preferably up to third
week of October.
• Use of balance dose of fertilizer.
• Releasing and rearing of predator like ladybird
beetle.
• Spray Rogor (dimethoate) 30 EC @1ml/liter of
water.
37. Cutworms, Agrotis segetum/ Agrotis
ipsilon (Lepidoptera: Noctuidae)
• This is important pest of worldwide occurrence.
• This is polyphagus pest reported from potato, tobacco, peas, wheat,
lentil, mustard, linseed, maize, sugarcane, cucurbits, bhang etc.
• The damage caused by caterpillar only.
• The slightly yellowish caterpillar on emergence is 1.5mm long with a
shiny, black head and a black shield on the prothorax.
• The full grown larva is about 42-45 mm long and is dark or dark brown
with a plump and greasy body.
• The adult moth measures about 25 mm from the head to the tip of the
abdomen and looks dark or blackish with some greyish patches on the
back and dark streaks on the fore wings.
• A. ipsilon is more darker than A. Segetum.
38. Life Cycle:
• The pest is active from October to April and probably
migrates to the mountains for further breeding during
summer.
• The moths appear in the plains in October and come out at
dusk and fly about until darkness sets in.
• They oviposit at night & lay creamy-white, dome shaped
eggs in clusters of about 30 each, either on the undersurface
of leaves of food plants or in the soil.
• The number of eggs laid by female varies from 199 to 344.
• Oviposition continues from 5 to 11 days and the duration of
the egg stage varies from 2 days in summer to 8-13 days in
winter.
• The newly hatched larvae feed on their egg- shells and move
like a semilooper.
• The larval stage varies from 30 to 34 days in February-April.
39. Continue life cycle
• The advanced stage larvae may become cannibalistic.
• The caterpillars are found throughout the winter and become active at
night when they cut off and fell the young plants.
• During the day, they hide in cracks and crevices in the soil.
• When full- grown, they make earthen chambers in the soil & pupate
underground.
• The pupal stage varies from 10 days in summer to 30 days in winter.
• The moths usually emerge at night.
• The life cycle is completed in 48-77 days and generally, 3 generation is
completed in a year.
• It is cold weathered pest and is active from October to March in the
plains.
• It suddenly disappears with the onset of summer during April and is not
traceable during the off-season from April to August-September.
40. Damage:
• The young larvae feed on the epidermis of the
leaves.
• As they grow, their habit changes.
• During the day time they live in cracks and holes
in the ground and come out at night and fell the
plants by cutting their stems, either below the
surface or above the ground.
• The cut branches are sometimes seen to have
been dragged into the holes where the leaves are
eaten at leisure.
• The larvae may also bore into cabbage.
41. Management:
• Collect and destroy caterpillar mechanically as they may be curled near the base of
young plants or just a few inches into the soil.
• Encourage predatory birds to visit on the field by placing birdbaths and feeder near the
planting beds.
• Expose hibernating stages of the cutworm into scorching sunlight and predatory birds.
• Place piles of weeds in the crop field as caterpillars hide inside the piles of weeds to
remain protected from day light & Collect and destroy the hidden caterpillar at morning.
• Irrigates field regularly.
• Broadcast Bt mixed bait (2gm Bacillus thuringiensis formulation with 1 kg of wheat
bran)@ 10 kg of bait per ha.
• Broadcast pesticide mixed bait (mixing @2g Malathion 5%dust with 1 kg of wheat
bran.)@10 kg bait/ha
• Treat soil with Dursban 10%G (Chloropyrifos) @20 kg per ha before planting.
• Spray cypermethrin (10% EC) or deltamethrin (10% EC) @1.5 ml per liter of water to
manage moth and early instars of cutworms.
• Drench the soil around the plants with cholorpyriphos 20 EC @ 2.5 Liter in 1000 liters of
of water/ha.
42. Tobbaco caterpillar, Spodoptera litura
(Lepidoptera: Noctuidae)
• The tobacco caterpillar is found throughout the tropical and
subtropical parts of the worlds.
• It is widespread and polyphagous, feeds on cabbage,
cauliflower, tomato, cowpea, sunflower, groundnut, etc.
• The damage is done only by the caterpillars, which measure
35-40 mm in length at maturity.
• They are velvety black with yellowish green dorsal stripes
and lateral white bands.
• The moth are about 22mm long and measure 40 mm across
the spread wings.
• The fore wings have beautiful golden and greyish brown
pattern.
45. Life cycle:
• This pest breeds throughout the year, although its development is
considerably retarded during winter.
• The moths are active at night when they mate and the female lays
about 300 eggs in clusters.
• These clusters are covered over by brown hair and they hatch in about
3-5 days.
• The larva feed gregariously form the first few days and then disperse to
feed individually.
• They pass through 6 stages and are full fed in 15-30 days.
• The full grown larvae enter the soil where they pupate.
• The pupal stage lasts 7-15 days and the moths, on emergence, live for
7-10 days.
• The life cycle is completed in 32-60 days and the pest completes eight
generations in a year.
46. Damage:
• The larvae feed on leaves and fresh growth.
They are mostly active at night and cause
extensive damage.
47. Management:
• Remove egg masses and clusters of larvae and
destroy them.
• Spray commercial formulation of Bacillus
thuringiensis @1-2 g/liter of water
• Spray 1 liter of malathion 50EC in 250 liters of
water per ha. Repeat spraying at 10 day
interval if necessary.
